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Home >> Saturn >> 2000 >> LS Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P0622: Generator "F" Terminal Circuit >> Diagnostic Procedures
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Diagnostic Procedures

  1. Perform On-Board Diagnostic (OBD) system check. See ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM. After performing OBD system check, go to next step.
  2. Start engine. Using scan tool, monitor generator "F" terminal status. Rev engine RPM up and down. If scan tool reading is constantly zero, go to step  4. If scan tool reading is constantly percent, go to next step. If scan tool reading is not constantly zero or 99 percent, problem is intermittent.
  3. Turn ignition off. Disconnect generator 2-pin harness connector. Turn ignition on, with engine off. If scan tool reading is zero percent, replace generator. If scan tool reading is not zero percent, check for short to voltage in generator harness connector terminal No. 1 (Red wire) circuit. Repair as necessary. If circuit is okay, replace PCM.
  4. Turn ignition off. Disconnect generator 2-pin harness connector. Using a fused jumper wire, connect jumper wire between battery voltage and harness connector terminal No. 2 (Gray wire). Turn ignition on. Observe scan tool reading. If scan tool reading is not 99 percent, go to next step. If scan tool reading is 99 percent, check for terminal tightness at harness connector. Repair as necessary. If terminals are okay, replace generator.
  5. Check fuse in jumper wire. If fuse is blown, check Gray wire circuit for short to ground. Repair as necessary. If circuit is okay, replace PCM. If fuse in jumper wire is okay, check Gray wire circuit for open or terminal tightness. Repair as necessary. If circuit or terminals are okay, replace PCM.
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